Discussion
On October 17, 2007, we issued a proposal to amend part 39 of the Federal Aviation Regulations (14 CFR part 39) to include an AD that would apply to certain Cessna Models 172R and 172S airplanes. This proposal was published in the Federal Register as a notice of proposed rulemaking (NPRM) on October 24, 2007 (72 FR 60291). The NPRM proposed to require you to detect and correct chafing of the fuel return line assembly.
Comments
We provided the public the opportunity to participate in developing this AD. We received no comments on the proposal or on the determination of the cost to the public.
Conclusion
We have carefully reviewed the available data and determined that air safety and the public interest require adopting the AD as proposed except for minor editorial corrections. We have determined that these minor corrections:
Are consistent with the intent that was proposed in the NPRM for correcting the unsafe condition; and
Do not add any additional burden upon the public than was already proposed in the NPRM.
Differences Between This AD and the Service Information
The service information permits tube damage up to a depth of 0.0035 inch. There is no known method to accurately measure the thickness damage on a tube. We require replacement of the fuel return line assembly if any damage is found.
If no chafing is found in the inspection of the fuel return line assembly, the service information does not require inspection for clearance around the fuel return line assembly. We require you to inspect the clearance between the fuel return line assembly and both the right steering tube assembly and airplane structure, for all applicable aircraft.
The service information does not specify a minimum clearance requirement between the fuel return line assembly and the right steering tube assembly, only that the fuel return line assembly does not touch either the right steering tube assembly orthe airplane structure. We require a minimum of 0.5 inch of clearance between the fuel return line assembly and both the right steering tube assembly and the airplane structure, during full rudder pedal actuation.
The requirements of this AD take precedence over the provisions in the service information.
Costs of Compliance
We estimate that this AD affects 928 airplanes in the U.S. registry.
We estimate the following costs to do the inspection:
Labor Cost
Parts Cost
Total Cost Per Airplane
Total Cost on U.S. Operators
1 work-hour X $80 per hour = $80
N/A
$80
$74,240
We estimate the following costs to do any necessary replacements that will be required based on the results of the inspection. We have no way of determining the number of airplanes that may need this replacement:
Labor Cost
Parts Cost
Total Cost Per Airplane
0.5 work-hour X $80 per hour = $40
$123
$163
Authority for This Rulemaking
Title 49 of the United States Code specifies the FAA's authority to issue rules on aviation safety. Subtitle I, Section 106 describes the authority of the FAA Administrator. Subtitle VII, Aviation Programs, describes in more detail the scope of the agency's authority.
We are issuing this rulemaking under the authority described in Subtitle VII, Part A, Subpart III, Section 44701, "General requirements.'' Under that section, Congress charges the FAA with promoting safe flight of civil aircraft in air commerce by prescribing regulations for practices, methods, and procedures the Administrator finds necessary for safety in air commerce. This regulation is within the scope of that authority because it addresses an unsafe condition that is likely to exist or develop on products identified in this AD.
Regulatory Findings
We have determined that this AD will not have federalism implications under Executive Order 13132. This AD will not have a substantial direct effect on the States, on the relationship between the national government and the States, or on the distribution of power and responsibilities among the various levels of government.
For the reasons discussed above, I certify that this AD:
1. Is not a "significant regulatory action'' under Executive Order 12866;
2. Is not a "significant rule'' under the DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979); and
3. Will not have a significant economic impact, positive or negative, on a substantial number of small entities under the criteria of the Regulatory Flexibility Act.
We prepared a summary of the costs to comply with this AD (and other information as included in the Regulatory Evaluation) and placed it in the AD Docket. You may get a copy of this summary by sending a request to us at the address listed under ADDRESSES. Include "Docket No. FAA-2007-29138; Directorate Identifier 2007-CE-073-AD'' in your request.
List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation safety, Incorporation by reference, Safety.
Adoption of the Amendment
Accordingly, under the authority delegated to me by the Administrator, the Federal Aviation Administration amends part 39 of the Federal Aviation Regulations (14 CFR part 39) as follows:
PART 39--AIRWORTHINESS DIRECTIVES
1. The authority citation for part 39 continues to read as follows:
Authority: 49 U.S.C. 106(g), 40113, 44701.
Sec. 39.13 [Amended]
2. FAA amends Sec. 39.13 by adding the following new AD: